The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.
(1) Field of the Invention
This invention generally relates to a flow meter strut.
More particularly, the invention relates to a flow meter strut having multiple flow meters mounted at different vertical locations on the strut.
(2) Description of the Prior Art
Currently with large piping systems, such as submarine launcher systems, it is difficult to measure velocity profiles and the corresponding volumetric flow rates during water slug firings due to the difficulty in modifying the ship board hardware to fix existing flow meter designs. Mounting a series of existing flow/velocity meters within the existing piping systems without modifying high pressure boundaries will greatly simplify the work required to get actual shipboard measurements. To date, only velocity and flow measurements made in controlled shore based facilities have been attainable using instruments that mount on the external surface of the pipes. This instrument will allow for shipboard measurement of the transient velocity and flow distributions within the torpedo tube launching system. Thus, a problem exists in the art whereby it is necessary to mount plural flow meters within a piping system without altering the piping system and enabling the use of known flow meters, particularly in a shipboard environment.
The following patents, for example, disclose various types of flow meters and their insertion into pipes, but do not disclose a flow meter strut assembly as described by the present invention.
U.S. Pat. No. 2,714,819 to Clark;
U.S. Pat. No. 3,748,901 to DeBaun;
U.S. Pat. No. 3,751,982 to Lambert;
U.S. Pat. No. 3,981,193 to Goulet;
U.S. Pat. No. 4,154,100 to Harbaugh et al.;
U.S. Pat. No. 4,562,745 to Parra;
U.S. Pat. No. 4,696,194 to Taylor;
U.S. Pat. No. 5,817,950 to Wiklund et al.;
U.S. Pat. No. 6,012,340 to Pounder et al.; and
U.S. Pat. No. 6,109,116 to Pelczynski.
Specifically, Clark discloses a fluid velocity measuring instrument having a plurality of means positioned in the path of fluid flow each adapted to transmit pressure as a function of the velocity of fluid flow thereat; means for averaging the velocity of the flow comprising a plurality of containers having liquid therein at a common liquid level, with each of the containers being connected to a different one of the pressures and thereby to displace liquid from the containers, with each container being shaped to cause the displacement of liquid therefrom in volumes which are a power of the pressures transmitted thereto; a receptacle in liquid communication with each of the containers to receive liquid in a volume equal to the total amount of liquid so displaced; means for vertically adjusting the receptacle; and indexing means associated with the receptacle and the containers to provide a reference for adjusting the receptacle to equalize the level of the liquid in the containers and the receptacle before and in the receptacle after liquid is displaced from the containers by the pressure.
The patent to DeBaun discloses an air balancing hood for collecting air discharged to the atmosphere from air diffusers, grilles, etc., such as those used in typical heating, ventilation and air-conditioning systems, in a convergent collection chamber which terminates in an air-straightening neck of known cross-section to eliminate turbulence and thereby achieve substantially laminar air flow for delivery to flow measuring instrumentation. The volume of air passing through the diffuser is directly measured by total pressure measuring means assembled to the hood and calibrated in flow rate units.
Lambert discloses a fluid flow meter head for installation in a duct to measure the fluid flow therein and thereafter to control the fluid flow rate therein, and includes an elongated hollow tubular member mounted in the flow of fluid in the duct, the member having spaced walls extending rearwardly therefrom to create a low pressure space therebetween, a central wall therein dividing the hollow member into two separate chambers, a series of axially spaced openings in the member facing the flow of fluid and opening into one of the chambers to provide a total pressure sensing chamber, a series of spaced openings in the member facing across the flow of fluid and opening to the second chamber to provide a static pressure sensing chamber, and fluid connecting means from each chamber to a means for measuring differential pressure to provide an indication for the air flow and to control the air flow rate.
Goulet discloses an apparatus for permanent installation in a heating or air conditioning duct to sense total and static pressure of air flowing therethrough. Plural manifolds are arranged within the duct to sense total pressure at a number of selected locations in a transverse plane of the duct. The plurality of manifolds communicates with a connecting manifold either directly or through sensing tubes arranged axially within the manifold tubes. Static pressure is also sensed at a plurality of preselected locations in the duct and communicated to at least one additional manifold tube arranged within the duct. Total and static pressure are communicated through single openings in the duct wall for attachment exteriorly thereof to an appropriate measuring instrument.
The patent to Harbaugh et al. discloses a method for stabilizing the pressure sensed by the downstream-facing port of a pitot tube type flow meter over a broad flow range, thereby providing a stable and repeatable flow coefficient. The invention comprises localizing the areas of boundary layer separation across deflecting surfaces located upstream of the port by sharply contouring the edges thereof and directing the flowing stream there across, and preventing reattachment of the boundary layer by positioning and contouring the surfaces containing the port downstream of the sharply contoured edges so as to continuously lie within the wake of the fluid flowing around the latter over a broad range of flow rates. The invention also encompasses the improved averaging pitot-type flow meter characterized by flow deflecting means having sharply contoured edges on both sides thereof effective to fix the location at which boundary layer separation occurs over a broad range of laminar and turbulent flow conditions, an upstream-facing impact surface shaped to direct the flowing fluid across the sharply contoured edges, and a downstream pressure so contoured and positioned relative to the sharply contoured edges as to cooperate there within preventing reattachment of the boundary layer under varying flow conditions.
Parra discloses a flow meter for insertion in a fluid conduit, the flow meter comprising a tubular member for the passage there through of a fluid which flows through the conduit and whose flow rate is to be measured; a bluff body which is mounted in the tubular member so as to produce in the fluid oscillations whose frequency varies with the flow rate; sensor means responsive to the fluid oscillations for indicating the flow rate, and vortex reducing means for reducing the separation of vortices from the tubular external surface of the tubular member.
The patent to Taylor discloses a sensing probe for use in determining fluid flow rates along a duct and comprises a probe pipe mounted within a wall of the duct to extend there across. Plural total pressure orifices are provided through the probe wall, to face fluid flow, and a single static pressure opening is provided on the downstream side of the probe. An averaging tube is mounted within the pipe and has two openings suitably disposed with respect to the duct axis so that the pressure within the averaging tube closely approximates to the average total pressure of the flow rate determination. The static pressure orifice communicates with a further tube within the pipe, to allow sensing of a pressure directly related to the actual static pressure.
Wiklund et al. discloses a transmitter in a process control system for measuring flow rate. The transmitter measures total pressure and differential pressure of process fluid flowing through a process pipe. The static pressure is determined based upon the total pressure. The calculated static pressure is used to determine the fluid density and the gas expansion factor of the process fluid flowing in the pipe. This information is used to calculate flow rate of the process fluid.
Pounder discloses an insertion-type fluid flow meter for measuring the flow rate of a fluid flowing through a conduit, wherein the flow meter incorporates a strut-mounted rotor having just one or two blades such that it can rotate through a circular area of diameter substantially larger than the maximum dimension of an opening in the conduit wall through which the strut extends. This minimizes the size of the opening, which simplifies its sealing. In addition, the support and the strut are configured such that the strut is releasably secured to the support by a snap fit, to facilitate a convenient replacement of the strut and attached rotor as the need might arise. The flow meter further incorporates a special set of ring-shaped spacers, to facilitate a convenient adjustment of the distance by which the strut projects into the conduit.
Pelczynski discloses a method and apparatus for use in installing a thorough-the-wall sensing device in a laboratory fume hood. The apparatus includes a sample tube with an outlet and a plurality of apertures and the tube is interconnected to an anemometer. The method includes placing the outlet in a number of positions inside of the fume hood to simulate a sidewall adapter for a through-the-wall sensing device in order to locate an optimum position for a through-the-wall sensing device. The method also includes fixing the sample tube in a number of positions within the fume hood while variably covering some of the apertures to simulate numerous locations and configurations for an averaging tube used with a through-the-wall sensing device. Therefore, an optimum location and configuration for an averaging tube can be readily determined.
It should be understood that the present invention would in fact enhance the functionality of the above patents by providing a flow meter strut assembly which is entirely housed within a piping system, is adjustable to fit an inner diameter of any piping system, and incorporates known flow meter instruments.
Therefore it is an object of this invention to provide a longitudinally adjustable flow meter strut assembly.
Another object of this invention is to provide a longitudinally adjustable flow meter strut assembly and utilize known flow meter instruments therewith.
Still another object of this invention is to provide a longitudinally adjustable flow meter strut assembly in which flow meter instruments are removably mounted on the strut portion of the flow meter strut assembly.
A still further object of the invention is to provide a flow meter strut assembly universally applicable to a variety of flow situations.
Yet another object of this invention is to provide a flow meter strut assembly having a fully internal mountable flow meter instrument.
In accordance with one aspect of this invention, there is provided a flow meter strut assembly including a strut portion having a first end plate, a second end plate, a longitudinally adjustable flow meter support structure between the first and second end plates, and curved mounting surfaces formed on outer surfaces of each of the first and second end plates of the strut portion. At least one flow meter is adjustably mounted on the flow meter support structure. The flow meter support structure is adjustable longitudinally by a turnbuckle assembly connected between the flow meter support structure and the second end plate.